From 374f2dab9cd7bd26bca73ef93cf75ed919d278f4 Mon Sep 17 00:00:00 2001

Message-Id: <374f2dab9cd7bd26bca73ef93cf75ed919d278f4.1389014116.git.minovotn@redhat.com>

In-Reply-To: <c8cc35838d42aa286242772d97e3a9be7bb786ba.1389014116.git.minovotn@redhat.com>

References: <c8cc35838d42aa286242772d97e3a9be7bb786ba.1389014116.git.minovotn@redhat.com>

From: Paolo Bonzini <pbonzini@redhat.com>

Date: Mon, 9 Dec 2013 14:09:11 +0100

Subject: [PATCH 23/50] block: generalize BlockLimits handling to cover

 bdrv_aio_discard too

RH-Author: Paolo Bonzini <pbonzini@redhat.com>

Message-id: <1386598178-11845-26-git-send-email-pbonzini@redhat.com>

Patchwork-id: 56062

O-Subject: [RHEL 7.0 qemu-kvm PATCH 25/52] block: generalize BlockLimits handling to cover bdrv_aio_discard too

Bugzilla: 1007815

RH-Acked-by: Jeffrey Cody <jcody@redhat.com>

RH-Acked-by: Fam Zheng <famz@redhat.com>

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

bdrv_co_discard is only covering drivers which have a .bdrv_co_discard()

implementation, but not those with .bdrv_aio_discard(). Not very nice,

and easy to avoid.

Suggested-by: Kevin Wolf <kwolf@redhat.com>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Peter Lieven <pl@kamp.de>

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

(cherry picked from commit d51e9fe505f7c7b97762100dd0e42cef43c90524)

---

 block.c | 80 +++++++++++++++++++++++++++++++++--------------------------------

 1 file changed, 41 insertions(+), 39 deletions(-)

Signed-off-by: Michal Novotny <minovotn@redhat.com>

---

 block.c | 80 +++++++++++++++++++++++++++++++++--------------------------------

 1 file changed, 41 insertions(+), 39 deletions(-)

diff --git a/block.c b/block.c

index 60484a6..8dfc207 100644

--- a/block.c

+++ b/block.c

@@ -4469,6 +4469,8 @@ static void coroutine_fn bdrv_discard_co_entry(void *opaque)

 int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,

                                  int nb_sectors)

 {

+    int max_discard;

+

     if (!bs->drv) {

         return -ENOMEDIUM;

     } else if (bdrv_check_request(bs, sector_num, nb_sectors)) {

@@ -4486,55 +4488,55 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,

         return 0;

     }

-    if (bs->drv->bdrv_co_discard) {

-        int max_discard = bs->bl.max_discard ?

-                          bs->bl.max_discard : MAX_DISCARD_DEFAULT;

+    if (!bs->drv->bdrv_co_discard && !bs->drv->bdrv_aio_discard) {

+        return 0;

+    }

-        while (nb_sectors > 0) {

-            int ret;

-            int num = nb_sectors;

+    max_discard = bs->bl.max_discard ?  bs->bl.max_discard : MAX_DISCARD_DEFAULT;

+    while (nb_sectors > 0) {

+        int ret;

+        int num = nb_sectors;

-            /* align request */

-            if (bs->bl.discard_alignment &&

-                num >= bs->bl.discard_alignment &&

-                sector_num % bs->bl.discard_alignment) {

-                if (num > bs->bl.discard_alignment) {

-                    num = bs->bl.discard_alignment;

-                }

-                num -= sector_num % bs->bl.discard_alignment;

+        /* align request */

+        if (bs->bl.discard_alignment &&

+            num >= bs->bl.discard_alignment &&

+            sector_num % bs->bl.discard_alignment) {

+            if (num > bs->bl.discard_alignment) {

+                num = bs->bl.discard_alignment;

             }

+            num -= sector_num % bs->bl.discard_alignment;

+        }

-            /* limit request size */

-            if (num > max_discard) {

-                num = max_discard;

-            }

+        /* limit request size */

+        if (num > max_discard) {

+            num = max_discard;

+        }

+        if (bs->drv->bdrv_co_discard) {

             ret = bs->drv->bdrv_co_discard(bs, sector_num, num);

-            if (ret) {

-                return ret;

+        } else {

+            BlockDriverAIOCB *acb;

+            CoroutineIOCompletion co = {

+                .coroutine = qemu_coroutine_self(),

+            };

+

+            acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors,

+                                            bdrv_co_io_em_complete, &co);

+            if (acb == NULL) {

+                return -EIO;

+            } else {

+                qemu_coroutine_yield();

+                ret = co.ret;

             }

-

-            sector_num += num;

-            nb_sectors -= num;

         }

-        return 0;

-    } else if (bs->drv->bdrv_aio_discard) {

-        BlockDriverAIOCB *acb;

-        CoroutineIOCompletion co = {

-            .coroutine = qemu_coroutine_self(),

-        };

-

-        acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors,

-                                        bdrv_co_io_em_complete, &co);

-        if (acb == NULL) {

-            return -EIO;

-        } else {

-            qemu_coroutine_yield();

-            return co.ret;

+        if (ret) {

+            return ret;

         }

-    } else {

-        return 0;

+

+        sector_num += num;

+        nb_sectors -= num;

     }

+    return 0;

 }

 int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors)

-- 

1.7.11.7